Initial attept at supporting Line Spectral Pairs. Various issues remain, and the ffmpeg decoder itself often fails on certain valid LSP files. Expect some issues.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@14134 a1c6a512-1295-4272-9138-f99709370657

3 files changed, 125 insertions, 78 deletions

diff --git a/apps/codecs/libwma/wmadata.h b/apps/codecs/libwma/wmadata.h
index d470d14581..7e2b6dd4a0 100644
--- a/apps/codecs/libwma/wmadata.h
+++ b/apps/codecs/libwma/wmadata.h
@@ -1425,9 +1425,10 @@ static const CoefVLCTable coef_vlcs[6] = {
     },
 };
 
-
+/*table of the values of 10^(index*.05)*/
 const fixed64 pow_table[] =
-    {
+    {   0x199a, 0x1cb9, 0x203a, 0x2429, 0x2893, 0x2d86, 0x3314, 0x3950, 0x404e, 0x4827,
+        0x50f4, 0x5ad5, 0x65ea, 0x725a, 0x804e, 0x8ff6, 0xa186, 0xb53c, 0xcb59, 0xe429,
         0x10000LL,0x11f3dLL,0x14249LL,0x1699cLL,0x195bcLL,0x1c73dLL,0x1fec9LL,0x23d1dLL,0x2830bLL,0x2d182LL,
         0x3298bLL,0x38c53LL,0x3fb28LL,0x47783LL,0x5030aLL,0x59f98LL,0x64f40LL,0x71457LL,0x7f17bLL,0x8e99aLL,
         0xa0000LL,0xb385eLL,0xc96d9LL,0xe2019LL,0xfd954LL,0x11c865LL,0x13f3dfLL,0x166320LL,0x191e6eLL,0x1c2f10LL,
@@ -1479,46 +1480,69 @@ const fixed32 pow_a_table[] =
 0x12fe,0x1307
 };
 
+
+/* 32.32 unsigned fixed format */
+/* This is a table of exponent values for an IEEE SP float.  Theres never anything less then about index 115
+ * making the size of this table fairly ridiculous.
+ */
+
+
 const fixed64 lsp_pow_e_table[] =
 {
-    0xf333f9deLL,        0xf0518db9LL,        0x0LL,        0x7e656b4fLL,        0x7999fcefLL,        0xf828c6dcLL,        0x0LL,
-    0x3f32b5a7LL,   0x3cccfe78LL,    0xfc14636eLL,    0x0LL,    0x9f995ad4LL,    0x9e667f3cLL,    0xfe0a31b7LL,
-    0x0LL,    0x4fccad6aLL,    0x4f333f9eLL,    0x7f0518dcLL,    0x0LL,    0x27e656b5LL,    0x27999fcfLL,
-    0xbf828c6eLL,    0x0LL,    0x13f32b5aLL,    0x13cccfe7LL,    0xdfc14637LL,    0x0LL,    0x89f995adLL,
-    0x9e667f4LL,    0x6fe0a31bLL,    0x0LL,    0x44fccad7LL,    0x4f333faLL,    0x37f0518eLL,    0x0LL,
-    0xa27e656bLL,    0x827999fdLL,    0x1bf828c7LL,    0x0LL,    0xd13f32b6LL,    0x413cccfeLL,    0xdfc1463LL,
-    0x0LL,    0xe89f995bLL,    0xa09e667fLL,    0x6fe0a32LL,    0x0LL,    0x744fccadLL,    0x504f3340LL,
-    0x837f0519LL,    0x0LL,    0xba27e657LL,    0xa82799a0LL,    0xc1bf828cLL,    0x0LL,    0x5d13f32bLL,
-    0xd413ccd0LL,    0x60dfc146LL,    0x0LL,    0xae89f996LL,    0x6a09e668LL,    0x306fe0a3LL,    0x0LL,
-    0xd744fccbLL,    0xb504f334LL,    0x9837f052LL,    0x80000000LL,    0x6ba27e65LL,    0x5a82799aLL,
-    0x4c1bf829LL,    0x40000000LL,    0x35d13f33LL,    0x2d413ccdLL,    0x260dfc14LL,    0x20000000LL,
-    0x1ae89f99LL,    0x16a09e66LL,    0x1306fe0aLL,    0x10000000LL,    0xd744fcdLL,    0xb504f33LL,
-    0x9837f05LL,    0x8000000LL,    0x6ba27e6LL,    0x5a8279aLL,    0x4c1bf83LL,    0x4000000LL,
-    0x35d13f3LL,    0x2d413cdLL,    0x260dfc1LL,    0x2000000LL,    0x1ae89faLL,    0x16a09e6LL,
-    0x1306fe1LL,    0x1000000LL,    0xd744fdLL,    0xb504f3LL,    0x9837f0LL,    0x800000LL,
-    0x6ba27eLL,    0x5a827aLL,    0x4c1bf8LL,    0x400000LL,    0x35d13fLL,    0x2d413dLL,
-    0x260dfcLL,    0x200000LL,    0x1ae8a0LL,    0x16a09eLL,    0x1306feLL,    0x100000LL,
-    0xd7450LL,    0xb504fLL,    0x9837fLL,    0x80000LL,    0x6ba28LL,    0x5a828LL,    0x4c1c0LL,
-    0x40000LL,    0x35d14LL,    0x2d414LL,    0x260e0LL,    0x20000LL,    0x1ae8aLL,    0x16a0aLL,
-    0x13070LL,    0x10000LL,    0xd745LL,    0xb505LL,    0x9838LL,    0x8000LL,    0x6ba2LL,
-    0x5a82LL,    0x4c1cLL,    0x4000LL,    0x35d1LL,    0x2d41LL,    0x260eLL,    0x2000LL,
-    0x1ae9LL,    0x16a1LL,    0x1307LL,    0x1000LL,    0xd74LL,    0xb50LL,    0x983LL,    0x800LL,
-    0x6baLL,    0x5a8LL,    0x4c2LL,    0x400LL,    0x35dLL,    0x2d4LL,    0x261LL,    0x200LL,    0x1afLL,
-    0x16aLL,    0x130LL,    0x100LL,    0xd7LL,    0xb5LL,    0x98LL,    0x80LL,    0x6cLL,    0x5bLL,
-    0x4cLL,    0x40LL,    0x36LL,    0x2dLL,    0x26LL,    0x20LL,    0x1bLL,    0x17LL,    0x13LL,
-    0x10LL,    0xdLL,    0xbLL,    0xaLL,    0x8LL,    0x7LL,    0x6LL,    0x5LL,    0x4LL,    0x3LL,
-    0x3LL,    0x2LL,    0x2LL,    0x2LL,    0x1LL,    0x1LL,    0x1LL,    0x1LL,    0x1LL,    0x1LL,
-    0x1LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,
-    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,
-    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,
-    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,
-    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,
-    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,    0x0LL,
-    0x0LL,    0x0LL
+        0xb504f30000000000LL, 0x9837f00000000000LL, 0x8000000000000000LL, 0x6ba27e8000000000LL, 0x5a82798000000000LL,
+        0x4c1bf80000000000LL, 0x4000000000000000LL, 0x35d13f4000000000LL, 0x2d413cc000000000LL, 0x260dfc0000000000LL,
+        0x2000000000000000LL, 0x1ae89fa000000000LL, 0x16a09e6000000000LL, 0x1306fe0000000000LL, 0x1000000000000000LL,
+        0xd744fd000000000LL, 0xb504f3000000000LL, 0x9837f0000000000LL, 0x800000000000000LL, 0x6ba27e800000000LL,
+        0x5a8279800000000LL, 0x4c1bf8000000000LL, 0x400000000000000LL, 0x35d13f400000000LL, 0x2d413cc00000000LL,
+        0x260dfc000000000LL, 0x200000000000000LL, 0x1ae89fa00000000LL, 0x16a09e600000000LL, 0x1306fe000000000LL,
+        0x100000000000000LL, 0xd744fd00000000LL, 0xb504f300000000LL, 0x9837f000000000LL, 0x80000000000000LL,
+        0x6ba27e80000000LL, 0x5a827980000000LL, 0x4c1bf800000000LL, 0x40000000000000LL, 0x35d13f40000000LL,
+        0x2d413cc0000000LL, 0x260dfc00000000LL, 0x20000000000000LL, 0x1ae89fa0000000LL, 0x16a09e60000000LL,
+        0x1306fe00000000LL, 0x10000000000000LL, 0xd744fd0000000LL, 0xb504f30000000LL, 0x9837f00000000LL,
+        0x8000000000000LL, 0x6ba27e8000000LL, 0x5a82798000000LL, 0x4c1bf80000000LL, 0x4000000000000LL,
+        0x35d13f4000000LL, 0x2d413cc000000LL, 0x260dfc0000000LL, 0x2000000000000LL, 0x1ae89fa000000LL,
+        0x16a09e6000000LL, 0x1306fe0000000LL, 0x1000000000000LL, 0xd744fd000000LL, 0xb504f3000000LL,
+        0x9837f0000000LL, 0x800000000000LL, 0x6ba27e800000LL, 0x5a8279800000LL, 0x4c1bf8000000LL,
+        0x400000000000LL, 0x35d13f400000LL, 0x2d413cc00000LL, 0x260dfc000000LL, 0x200000000000LL,
+        0x1ae89fa00000LL, 0x16a09e600000LL, 0x1306fe000000LL, 0x100000000000LL, 0xd744fd00000LL,
+        0xb504f300000LL, 0x9837f000000LL, 0x80000000000LL, 0x6ba27e80000LL, 0x5a827980000LL,
+        0x4c1bf800000LL, 0x40000000000LL, 0x35d13f40000LL, 0x2d413cc0000LL, 0x260dfc00000LL,
+        0x20000000000LL, 0x1ae89fa0000LL, 0x16a09e60000LL, 0x1306fe00000LL, 0x10000000000LL,
+        0xd744fd0000LL, 0xb504f30000LL, 0x9837f00000LL, 0x8000000000LL, 0x6ba27e8000LL,
+        0x5a82798000LL, 0x4c1bf80000LL, 0x4000000000LL, 0x35d13f4000LL, 0x2d413cc000LL,
+        0x260dfc0000LL, 0x2000000000LL, 0x1ae89fa000LL, 0x16a09e6000LL, 0x1306fe0000LL,
+        0x1000000000LL, 0xd744fd000LL, 0xb504f3000LL, 0x9837f0000LL, 0x800000000LL,
+        0x6ba27e800LL, 0x5a8279800LL, 0x4c1bf8000LL, 0x400000000LL, 0x35d13f400LL,
+        0x2d413cc00LL, 0x260dfc000LL, 0x200000000LL, 0x1ae89fa00LL, 0x16a09e600LL,
+        0x1306fe000LL, 0x100000000LL, 0xd744fd00LL, 0xb504f300LL, 0x9837f000LL,
+        0x80000000LL, 0x6ba27e80LL, 0x5a827980LL, 0x4c1bf800LL, 0x40000000LL,
+        0x35d13f40LL, 0x2d413cc0LL, 0x260dfc00LL, 0x20000000LL, 0x1ae89fa0LL,
+        0x16a09e60LL, 0x1306fe00LL, 0x10000000LL, 0xd744fd0LL, 0xb504f30LL,
+        0x9837f00LL, 0x8000000LL, 0x6ba27e8LL, 0x5a82798LL, 0x4c1bf80LL,
+        0x4000000LL, 0x35d13f4LL, 0x2d413ccLL, 0x260dfc0LL, 0x2000000LL,
+        0x1ae89faLL, 0x16a09e6LL, 0x1306fe0LL, 0x1000000LL, 0xd744fdLL,
+        0xb504f3LL, 0x9837f0LL, 0x800000LL, 0x6ba27eLL, 0x5a8279LL,
+        0x4c1bf8LL, 0x400000LL, 0x35d13fLL, 0x2d413cLL, 0x260dfcLL,
+        0x200000LL, 0x1ae89fLL, 0x16a09eLL, 0x1306feLL, 0x100000LL,
+        0xd744fLL, 0xb504fLL, 0x9837fLL, 0x80000LL, 0x6ba27LL,
+        0x5a827LL, 0x4c1bfLL, 0x40000LL, 0x35d13LL, 0x2d413LL,
+        0x260dfLL, 0x20000LL, 0x1ae89LL, 0x16a09LL, 0x1306fLL,
+        0x10000LL, 0xd744LL, 0xb504LL, 0x9837LL, 0x8000LL,
+        0x6ba2LL, 0x5a82LL, 0x4c1bLL, 0x4000LL, 0x35d1LL,
+        0x2d41LL, 0x260dLL, 0x2000LL, 0x1ae8LL, 0x16a0LL,
+        0x1306LL, 0x1000LL, 0xd74LL, 0xb50LL, 0x983LL,
+        0x800LL, 0x6baLL, 0x5a8LL, 0x4c1LL, 0x400LL,
+        0x35dLL, 0x2d4LL, 0x260LL, 0x200LL, 0x1aeLL,
+        0x16aLL, 0x130LL, 0x100LL, 0xd7LL, 0xb5LL,
+        0x98LL, 0x80LL, 0x6bLL, 0x5aLL, 0x4cLL,
+        0x40LL, 0x35LL, 0x2dLL, 0x26LL, 0x20LL,
+        0x1aLL, 0x16LL, 0x13LL, 0x10LL, 0xdLL,
+        0xbLL, 0x9LL, 0x8LL, 0x6LL, 0x5LL,
+        0x4LL, 0x4LL, 0x3LL, 0x2LL, 0x2LL,
+        0x2LL, 0x1LL, 0x1LL, 0x1LL, 0x1LL,
+        0x0LL
 };
 
-
-
 /* table of exp noise values multiplied by 16 in order to reduce rounding error */
  fixed32 noisetable_exp[] =
 {
diff --git a/apps/codecs/libwma/wmadec.h b/apps/codecs/libwma/wmadec.h
index a3e4acdc94..8ae49eed0c 100644
--- a/apps/codecs/libwma/wmadec.h
+++ b/apps/codecs/libwma/wmadec.h
@@ -153,8 +153,8 @@ typedef struct WMADecodeContext
     /* lsp_to_curve tables */
     fixed32 lsp_cos_table[BLOCK_MAX_SIZE];
     fixed64 lsp_pow_e_table[256];
-    fixed64 lsp_pow_m_table1[(1 << LSP_POW_BITS)];
-    fixed64 lsp_pow_m_table2[(1 << LSP_POW_BITS)];
+    fixed32 lsp_pow_m_table1[(1 << LSP_POW_BITS)];
+    fixed32 lsp_pow_m_table2[(1 << LSP_POW_BITS)];
 
     /* State of current superframe decoding */
     int bit_offset;
diff --git a/apps/codecs/libwma/wmadeci.c b/apps/codecs/libwma/wmadeci.c
index ecde2fd034..552f85183c 100644
--- a/apps/codecs/libwma/wmadeci.c
+++ b/apps/codecs/libwma/wmadeci.c
@@ -286,10 +286,9 @@ int ff_mdct_init(MDCTContext *s, int nbits, int inverse)
     s->tsin[i] = - fsincos(ip<<16, &(s->tcos[i]));            //I can't remember why this works, but it seems to agree for ~24 bits, maybe more!
     s->tcos[i] *=-1;
   }
-      s->fft.nbits = s->nbits - 2;
+    (&s->fft)->nbits = nbits-2;
 
-
-    s->fft.inverse = inverse;
+    (&s->fft)->inverse = inverse;
 
     return 0;
 
@@ -733,8 +732,10 @@ int wma_decode_init(WMADecodeContext* s, asf_waveformatex_t *wfx)
             s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
             /* high freq computation */
 
-            fixed32 tmp = high_freq*2;
-            s->high_band_start[k] = fixtoi32(fixdiv32(tmp, itofix32(s->sample_rate)) *block_len +0x8000);
+            fixed32 tmp1 = high_freq*2;                 /* high_freq is a fixed32!*/
+            fixed32 tmp2=itofix32(s->sample_rate>>1);
+            s->high_band_start[k] = fixtoi32( fixdiv32(tmp1, tmp2) * (block_len>>1) +0x8000);
+
             /*
             s->high_band_start[k] = (int)((block_len * 2 * high_freq) /
                                           s->sample_rate + 0.5);*/
@@ -935,48 +936,57 @@ int wma_decode_init(WMADecodeContext* s, asf_waveformatex_t *wfx)
 static inline fixed32 pow_m1_4(WMADecodeContext *s, fixed32 x)
 {
     union {
-        fixed64 f;
+        float f;
         unsigned int v;
     } u, t;
     unsigned int e, m;
-    fixed64 a, b;
+    fixed32 a, b;
 
-    u.f = x;
+    u.f = fixtof64(x);
     e = u.v >> 23;
     m = (u.v >> (23 - LSP_POW_BITS)) & ((1 << LSP_POW_BITS) - 1);
     /* build interpolation scale: 1 <= t < 2. */
     t.v = ((u.v << LSP_POW_BITS) & ((1 << 23) - 1)) | (127 << 23);
     a = s->lsp_pow_m_table1[m];
     b = s->lsp_pow_m_table2[m];
-    return lsp_pow_e_table[e] * (a + b * t.f);
+
+        /*lsp_pow_e_table contains 32.32 format */
+        /*TODO:  Since we're unlikely have value that cover the whole
+         * IEEE754 range, we probably don't need to have all possible exponents*/
+
+    return (lsp_pow_e_table[e] * (a + fixmul32(b, ftofix32(t.f))) >>32);
 }
 
 static void wma_lsp_to_curve_init(WMADecodeContext *s, int frame_len)
 {
-    fixed32 wdel, a, b;
+    fixed32 wdel, a, b, temp, temp2;
     int i, m;
 
     wdel = fixdiv32(M_PI_F, itofix32(frame_len));
+    temp = fixdiv32(itofix32(1),     itofix32(frame_len));
     for (i=0; i<frame_len; ++i)
     {
-        s->lsp_cos_table[i] = 0x20000 * fixcos32(wdel * i);    //wdel*i between 0 and pi
+                /*TODO: can probably reuse the trig_init values here */
+        fsincos((temp*i)<<15, &temp2);
+        /*get 3 bits headroom + 1 bit from not doubleing the values*/
+        s->lsp_cos_table[i] = temp2>>3;
 
     }
-
-
     /* NOTE: these two tables are needed to avoid two operations in
        pow_m1_4 */
     b = itofix32(1);
     int ix = 0;
+
+    /*double check this later*/
     for(i=(1 << LSP_POW_BITS) - 1;i>=0;i--)
     {
         m = (1 << LSP_POW_BITS) + i;
-        a = m * (0x8000 / (1 << LSP_POW_BITS)); //PJJ
-        a = pow_a_table[ix++];  // PJJ : further refinement
+        a = pow_a_table[ix++]<<4;
         s->lsp_pow_m_table1[i] = 2 * a - b;
         s->lsp_pow_m_table2[i] = b - a;
         b = a;
     }
+
 }
 
 /* NOTE: We use the same code as Vorbis here */
@@ -988,27 +998,42 @@ static void wma_lsp_to_curve(WMADecodeContext *s,
                              fixed32 *lsp)
 {
     int i, j;
-    fixed32 p, q, w, v, val_max;
+    fixed32 p, q, w, v, val_max, temp, temp2;
 
     val_max = 0;
     for(i=0;i<n;++i)
     {
-        p = 0x8000;
-        q = 0x8000;
+                /* shift by 2 now to reduce rounding error,
+                 * we can renormalize right before pow_m1_4
+                 */
+
+        p = 0x8000<<5;
+        q = 0x8000<<5;
         w = s->lsp_cos_table[i];
+
         for (j=1;j<NB_LSP_COEFS;j+=2)
         {
-            q *= w - lsp[j - 1];
-            p *= w - lsp[j];
+
+                         /*w is 5.27 format, lsp is in 16.16, temp2 becomes 5.27 format*/
+                        temp2 = ((w - (lsp[j - 1]<<11)));
+            temp = q;
+            /*q is 16.16 format, temp2 is 5.27, q becomes 16.16 */
+            q = fixmul32b(q, temp2 )<<4;
+                        p = fixmul32b(p, (w - (lsp[j]<<11)))<<4;
         }
-        p *= p * (0x20000 - w);
-        q *= q * (0x20000 + w);
-        v = p + q;
-        v = pow_m1_4(s, v); // PJJ
+
+                /* 2 in 5.27 format is 0x10000000 */
+        p = fixmul32(p, fixmul32b(p, (0x10000000 - w)))<<3;
+        q = fixmul32(q, fixmul32b(q, (0x10000000 + w)))<<3;
+
+        v = (p + q) >>9;  /* p/q end up as 16.16 */
+        v = pow_m1_4(s, v);
         if (v > val_max)
             val_max = v;
         out[i] = v;
+
     }
+
     *val_max_ptr = val_max;
 }
 
@@ -1392,13 +1417,11 @@ static int wma_decode_block(WMADecodeContext *s)
             coefs1 = s->coefs1[ch];
             exponents = s->exponents[ch];
             esize = s->exponents_bsize[ch];
-            mult = fixdiv64(pow_table[total_gain],Fixed32To64(s->max_exponent[ch]));
-         //   mul = fixtof64(pow_table[total_gain])/(s->block_len/2)/fixtof64(s->max_exponent[ch]);
-
+            mult = fixdiv64(pow_table[total_gain+20],Fixed32To64(s->max_exponent[ch]));
             mult = fixmul64byfixed(mult, mdct_norm);        //what the hell?  This is actually fixed64*2^16!
-            coefs = (*(s->coefs))[ch];                                            //VLC exponenents are used to get MDCT coef here!
+            coefs = (*(s->coefs))[ch];
 
-        n=0;
+                n=0;
 
             if (s->use_noise_coding)
             {
@@ -1428,8 +1451,9 @@ static int wma_decode_block(WMADecodeContext *s)
                         e2 = 0;
                         for(i = 0;i < n; ++i)
                         {
-                            v = exp_ptr[i]>>5;  /*v is noramlized later on so its fixed format is irrelevant*/
-                            e2 += fixmul32(v, v);
+                                                        /*v is noramlized later on so its fixed format is irrelevant*/
+                            v = exp_ptr[i]>>4;
+                            e2 += fixmul32(v, v)>>3;
                         }
                          exp_power[j] = e2/n; /*n is an int...*/
                         last_high_band = j;
@@ -1456,7 +1480,8 @@ static int wma_decode_block(WMADecodeContext *s)
                         fixed32 tmp = fixdiv32(exp_power[j],exp_power[last_high_band]);
                         mult1 = (fixed64)fixsqrt32(tmp);
                         /* XXX: use a table */
-                        mult1 = mult1 * pow_table[s->high_band_values[ch][j]] >> PRECISION;
+                        /*mult1 is 48.16, pow_table is 48.16*/
+                        mult1 = mult1 * pow_table[s->high_band_values[ch][j]+20] >> PRECISION;
 
                         /*this step has a fairly high degree of error for some reason*/
                                 mult1 = fixdiv64(mult1,fixmul32(s->max_exponent[ch],s->noise_mult));
@@ -1481,9 +1506,9 @@ static int wma_decode_block(WMADecodeContext *s)
 
                            /*don't forget to renormalize the noise*/
                                                    temp1 = (((int32_t)*coefs1++)<<16) + (noise>>4);
-                                                   temp2 = fixmul32(*exponents, mult>>16);
-                            *coefs++ = fixmul32(temp1, temp2)>>1;
-                            ++exponents;
+                                                   temp2 = fixmul32(*exponents, mult>>17);
+                           *coefs++ = fixmul32(temp1, temp2);
+                           ++exponents;
                         }
                     }
                 }
@@ -1637,10 +1662,8 @@ static int wma_decode_frame(WMADecodeContext *s, int16_t *samples)
 
         for (i=0;i<n;++i)
         {
-            a = fixtoi32(*iptr++)<<1;        //ugly but good enough for now
-
-
 
+                        a = fixtoi32(*iptr++)<<1;        //ugly but good enough for now
 
 
             if (a > 32767)